1315666720 has 144 divisors (see below), whose sum is σ = 3395505960. Its totient is φ = 481296384.

The previous prime is 1315666687. The next prime is 1315666747. The reversal of 1315666720 is 276665131.

It can be written as a sum of positive squares in 12 ways, for example, as 663783696 + 651883024 = 25764^2 + 25532^2 .

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a self number, because there is not a number n which added to its sum of digits gives 1315666720.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1710496 + ... + 1711264.

Almost surely, 2^1315666720 is an apocalyptic number.

1315666720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1315666720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1697752980).

1315666720 is an abundant number, since it is smaller than the sum of its proper divisors (2079839240).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1315666720 is a wasteful number, since it uses less digits than its factorization.

1315666720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 855 (or 830 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 37.

The square root of 1315666720 is about 36272.1204232672. The cubic root of 1315666720 is about 1095.7596308080.

The spelling of 1315666720 in words is "one billion, three hundred fifteen million, six hundred sixty-six thousand, seven hundred twenty".